Porsche Carrera Cup GB contender Karl Leonard has signed a last minute deal with the front-running MRS team for round three of the Porsche Mobil 1 Supercup at Silverstone this weekend (28-30 June).Widely regarded as the most competitive single-make GT championships in the world, the 2013 Porsche Mobil 1 Supercup Championship has attracted guest appearances from drivers like rally stars Sebastian Loeb and Sebastian Ogier. Meanwhile, championship regulars including Sean Edwards and Alain Menu further underline the quality of the grid in the Supercup.This is a very exciting opportunity for me, said Irishman Leonard. I've been having a really good run in Pro-Am1 in the Carrera Cup so far this season where Team Parker Racing has provided me with a superb class-winning car. However, the Supercup car is the 2013-specification car, so it will be a new challenge for me. That said, to race on a grid supporting the British Grand Prix at Silverstone is an honour in itself and I really cant wait to join up with the MRS team and make the most of this fantastic opportunity.Qualifying for the Porsche Mobil 1 Supercup at Silverstone starts at 11.25 on Saturday morning, with the race on Sunday at 10.45.